OBJECTIVE To explore the effect of basic fibroblast growth factor (bFGF) combined with autogenous vein graft conduit on peripheral nerve regeneration. METHODS Fifty four New Zealand rabbits were divided into three groups. The main trunk of sciatic nerve of rabbit in one side was severed and bridged by autogenous vein. 0.2 ml bFGF solution (4,000 U/ml) was intravenously injected to the vein graft conduit as group A, the same amount of saline solution as group B, and no solution injection as group C. Microscopic examination, axon video analysis and nerve conduct velocity were performed at the 10th, 30th, and 100th day after operation. RESULTS The nerve fibers were grown into vein graft conduit in all groups at 30th after operation, they were more and regular in group A than that of group B and C, and the axon regeneration rate in group A was more than that of group B and C. CONCLUSION bFGF combined with autogenous vein graft conduit can markedly promote nerve regeneration.
【Abstract】 Objective To reduce restenosis in vein grafts after coronary artery bypass grafting, to investigate theeffect of human tissue factor pathway inhibitor(TFPI) gene del ivery on neointima formation. Methods The eukaryotic expressed plasmid vector pCMV-(Kozak) TFPI was constructed. Forty-eight Japanese white rabbits were randomly divided into 3 groups with 16 rabbits in each group: TFPI group, empty plasmid control group and empty control group. Animal model of common carotid artery bypass grafting was constructed. Before anastomosis, vein endothel iocytes were transfected with cationic l iposome containing the plasmid pCMV- (Kozak) TFPI (400 μg) by pressurizing infusion (30 min) in TFPI group. In empty plasmid control group, vector pCMV- (Kozak) TFPI was replaced by empty plasmid pCMV (400 μg). In empty control group, those endothel iocytes were not interfered. After operation, vein grafts were harvested at 3 days for immunohistochemical, RTPCR and Western-blot analyses of exogenous gene expression and at 30 days for histopathology measurement of intimal areas, media areas and calculation of intimal/media areas ratio. Luminal diameter and vessel wall thickness were also measured byvessel Doppler ultrasonography and cellular category of neointima was analyzed by transmission electron microscope at 30 days after operation. Results Human TFPI mRNA and protein were detected in TFPI group. The mean luminal diameter of the TFPI group, empty plasmid control group and empty control group was (2.68 ± 0.32) mm, (2.41 ± 0.23) mm and (2.38 ± 0.21) mm respectively. There were statistically significant differences between TFPI group and control groups (P lt; 0.05). The vessel wall thickness of the TFPI group, empty plasmid control group and empty control group was (1.09 ± 0.11) mm, (1.28 ± 0.16) mm and (1.34 ± 0.14) mm respectively. There were statistically significant differences between TFPI group and other control groups (P lt; 0.01). The mean intimal areas, the ratio of the intimal/media areas of the TFPI group were (0.62 ± 0.05) mm2and 0.51 ± 0.08 respectively, which were reduced compared with those of the two control groups(P lt; 0.05). The mean media areas had no significant differences among three groups (P gt; 0.05). Through transmission electron microscope analyses, no smoothmuscle cells were seen in neointima of TFPI group in many visual fields, but smooth muscle cells were found in neointima of two control groups. Conclusion Human TFPI gene transfection reduced intimal thickness in vein grafts.
Objective To investigate the results and applicationvalue of crotch-shaped vein grafts in repairing defects of the vessels with a large diameter.Methods From June 1998 to October 2003, 35 cases of vesseldefects with a large diameter were repaired with crotch-shaped vein graft (29 males and 6 females,aged 18 to 45 years with an average of 25.7 years ). The locations of defects were femoral artery in 25 cases, popliteal artery in 2 cases, femoral vein in 7 cases, and subclavian vein in 1 case. The interval between injure and operatioinwas 1-8.5 hours (4.1 hours on average).The blood flows of trouble and healthy vascular were determined with Doppler detector and compared preoperatively andpostoperatively. Results All the anastomotic stomas were patent in 35 cases. Thirty-one cases were followed up 6 weeks to 24 months (9.5 months on average), the patent rate was 100%, no case occurred vasospasm or tromboembolism; 2 cases occurred stomal leak and became hematoma, 3 cases occurred muscular necrosis, and the 5 cases achieved primary healing after secondary operation. The Doppler results showed that there was statistically significant difference in the blood flow betweenpostoperation and preoperation (Plt;0.01), but no statistically significant difference when compared the trouble vascular after operation with healthy vascular (Pgt;0.05). Conclusion The methodof crotch-shaped vein grafts is safe and effective in repairing defects of vessels with a large diameter,which is easy to draw materials and handy to operate. It has a promising value in clinical application.
Abstract: Objective To investigate the effect of keeping implanted vein graft from restenosis by local application of paclitaxel. Methods Ninetysix New Zealand rabbits were randomly divided into three groups, control group (n=32), group Ⅰ(n=32), group Ⅱ(n=32). The vein graft stenosis model was made in all rabbits. In group Ⅰand group Ⅱ, 1μg and 8μg of paclitaxel was applied locally in pluronic gelatin respectively. There were no local treatment in control group. Grafts were harvested at 1, 2, 4, and 6 weeks and underwent morphological analysis as well as immunohistochemical analysis. Results The intimal thickness in group Ⅱ were significantly decreased compared to those in control group at 1,2,4, and 6 weeks after operation (30.10±4.50μm vs. 48.20±9.16μm, 40.70±6.91μm vs. 54.20±8.67μm, 54.70±7.11μm vs. 68.60±13.72μm, and 68.70±8.24μm vs. 76.40±12.98μm, Plt;0.05). The CD8 positive cells and metallothionein positive cells in group Ⅰand group Ⅱ were significantly decreased compared to those in control group (Plt;0.05). Conclusion The results suggest that perivascular application of paclitaxel inhibits neointimal hyperplasia of vein grafts in a rabbit model, and paclitaxel may have a therapeutic potential for the treatment of vein graft disease.
In order to solve the defect of blood vessel in tissue transplantation and complicated palmar amputation, bridge by "Y" type vein had been used from Jan. 1990 to Jul. 1996. Twenty-three cases were treated. In this series, there were 16 males and 7 females, with ages ranged from 10 to 42 years old. Six cases were the defect of lower legs anterior skin and tibia, 3 cases were the femur fracture with injury of femoral artery and tissue’s defect, 2 cases were defect of five fingers, 12 cases were complicated palmar amputation. RESULT: 15 cases with tissue transplantation and 12 cases with limb replantation were all survival without infection or necrosis. After the following-up for 3 years (ranged from 1 to 5 years), the function of injured limbs were satisfactory, 19 patients had resumed their original work. So, to bridge by "Y" type vein is a good method for repairing the defect of blood vessels in tissue transplantation and complicated palmar amputation, but skilled microsurgery technique is required.
Objective To study the mechanism of restenosis of the vein graft and the effect of the grafting injury to the vein graft. Methods One side of the 36 healthy rabbits was randomly chosen as the V-A group, and on the side a 1.5cmlong femoral vein was obtained, and an 0.5-cm-long segment of the obtained femoral vein was separated as the control group. The remaining 1-cm-long femoral vein was inverted and was autogenously implanted into the femoral artery on the same side of the rabbit. The other side of the rabbits was chosen as the V-V group, and on this side a 1-cm-long femoral vein was obtained ex vivo and then was sutured in situ. The vein grafts on both sides were harvested 4 weeks after operation. The specimens from the harvested vein grafts were stained with HE and theelastic fiber Victoria blue for an observation on the histological changes in the walls of the vein grafts, and the specimens were also stained by the immunohistochemistry of the proliferating cell nuclear antigen (PCNA) for an observation on the wall cell proliferation of the vein grafts. The changes in the ultrastructure of the proliferated wall cells of the vein grafts were observed under electron microscope. The two sides of the rabbits were compared. Results The smooth muscle cells of the media developed hyperplasia, but theintima and the media remained unchanged in their thickness (3.50±0.41 μm, 12.23±1.59 μm) in the V-V group, with no difference when compared with the control group (3.40±0.37 μm, 12.14±1.62 μm); however, when compared with the V-A group (25.60±3.21 μm, 21.30±2.47 μm),there was a significant difference in the thickness (Plt;0.01). There were no cells positive for PCNA by the immunohistochemistry examination in the control group. The cells positive for PCNA were found in the intima and the media in both the V-V group and the V-A group; however, the percentageof the cells positive for PCNA in the intima and the media was significantly greater in the V-A group than in the V-V group (16.4%±1.9% and 36.5%±3.7% vs 5.9%±1.3% and 23.4%±3.4%, Plt;0.01). In the V-V group, the endothelial cell could be observed under transmis-sion electron microscope, which was flat and had a processlike villus at its free end, and the endothelial cells were closely arranged andhad hyperplasia of the smooth muscle cells in the media. But in the V-A group,the endothelial cells had an obvious hyperplasia with an irregular shape and a widened space between the cells, and in the intima a great amount of the smooth muscle cells could be observed, which had a broken basement membrane. The smooth muscle cells also had an obvious hyperplasia in the media. The shape and alignment of the endothelial cells in the control group were similar to those in the V-V group, but the hyperplasia of the smooth muscle cells was not observed in the media. Conclusion The grafting injury can cause hyperplasia ofthe vascular wall cells, and if the hemodynamics is changed simultaneously, more serious hyperplasia and cell migration can be observed from the media to the intima, resultingin restenosis of the blood vessels. So, if we can reduce the grafting injury and improve the microcirculation of the vein graft, we may find out the methods ofpreventing restenosis of the vein graft. The animal model of the V-V graftcan help to understand the mechanism of restenosis of the vein graft.
In order to develope a new method to overcome the difficulties in anastomosis of blood vessels with different diameter, phleboplasty was utilized at the join-point to expand the diameter of branched vein graft, with a funnel-shaped stoma formed consequently. After successfully experimented in fresh blood vessels in vitro, the method was practised clinically to repair injured arteries in extremities, with the outcome that phleboplasty of branched vein graft could enlarge the diameter by 1-1.25 times, and with satisfied effects in 3 clinic cases. So, the conclusion was that: phleboplasty of branched vein graft was a new effective and convinient method to repair injured arteries with different diameters
OBJECTIVE: To investigate the relationship between the different defect length of vessels and the options of vascular repair, and to compare the different options of repair because of the longitudinal biomechanical effect. METHODS: A clinical analysis was undertaken to evaluate the major arterial and venous injuries in human extremities repaired by end-to-end anastomoses or venous autograft(177 cases, 185 vessels). Compared the defect length of the same kind of vessels repaired by different options (Student-t test). Evaluated the defect length to repair arterial injuries between by end-to-end anastomoses and by vein graft by means of 95% confidence interval. RESULTS: There was significant difference between the defect length of brachial artery repaired by end-to-end anastomosis and femoral artery and popliteal artery repaired by autogenous vein graft (P lt; 0.01). The upper limit of confidence interval in the defect length of brachial artery, femoral artery and popliteal artery was 3.17 cm, 2.81 cm and 2.44 cm respectively by end-to-end anastomosis by means of 95% confidence interval. The lower limit of confidence interval in the defect length of brachial artery, femoral artery and popliteal artery was 2.82 cm, 2.41 cm and 2.17 cm respectively by vein graft by means of 95% confidence interval. The defect length of brachial artery, femoral artery and popliteal artery repaired by vein graft was linear correlation with the length of graft. CONCLUSION: Because of the longitudinal biomechanical difference of arteries and veins in human extremities, different options of repair are necessary to different arterial injuries.
ObjectiveTo detect the inhibitory effect of early growth response gene-1 DNA enzyme (EDRz) on proliferation of vascular smooth muscle cell (VSMC) and intimal hyperplasia, and confirm the effect of gene therapy on stenosis and occlusion after vein transplantation. MethodsEDRz was constructed, and autogenous vein graft model was established with Wistar rats, transplanting the right jugular vein to infra renal abdominal aorta by microsurgical technique. EDRz was transfected to the graft veins and the vein graft samples were harvested at hour 1, 2, 6, 24 and on day 3, 7, 14, 28, 42 after grafting, 10 Wistar rats were randomly selected in every time. The expression of EDRz in transfected vein graft was detected by fluorescent microscope. Egr-1 mRNA was measured by reverse transcription-PCR (RT-PCR) and in situ hybridization, respectively. The protein expression of Egr-1 was detected by Western blot and immunohistochemistry, respectively. HE stained vein grafts were observed under microscope. Results① The results of EDRz transfected vein graft: At hour 1 after grafting, EDRz was mainly located in adventitia, tunica media, and partial endothelial cells of vein graft; At hour 2, 6, and 24, EDRz was located in tunica media of vein graft; and on day 7, it was mainly located in intima of vein graft. There wasn’t EDRz in vein grafts on day 14, 28, and 42. ② The results of expression of Egr-1 mRNA: Detection by RT-PCR: At hour 1 after transfecting, the expression of Egr-1 mRNA arrived at the peak, and declined at hour 2, 6, and 24. The expression was tenuity on day 3. Egr-1 mRNA expression was not found on day 7, 14, 28, and 42. The expression of Egr-1 mRNA at hour 1 was significantly higher than that of the other time point (Plt;0.01). The result of in situ hybridization was coincident with RT-PCR. ③ The results of expression of Egr-1 protein: The result of Western blot: There was no expression of Egr-1 protein in normal veins. At hour 2 after grafting, expression of Egr-1 protein was found, and declined at hour 6, 24, and on day 3. There was no expression of Egr-1 protein at hour 1, and on day 7, 14, 28, and 42. The expression of Egr-1 protein at hour 2 was significantly higher than that of the other time point (Plt;0.01). The result of immunohistochemistry was coincident with Western blot. ④The degree of VSMC hyperplasia and intimal thickness were lighter in EDRz transfected vein grafts than that in nottransfected vein grafts contemporarily. ConclusionsEDRz could reduce the expression of Egr-1 in autogenous vein graft, and could effectively restrain VSMC proliferation and intimal hyperplasia, and prevent vascular stenosis and occlusion after vein grafting.
Objective To study the effect of vein-occlusion on the replanted limb survival in SD rats at different stages. Methods Twenty-five adultSD rats were randomly divided into 5 groups according to the time of the femoral vein occlusion after the replanted limbs:2- ,3- ，4 -，6-，and 8- day groups. The limbs were observed through naked eye, measurement of dermal temperature and angiography. Results No formation of collateral veinlet was found, and necrosis wasseen in the replanted limbs of 2- , 3- day groups. Reflux-vein was gradually increased in the replanted limbs of 4，6，and 8 day groups. Angiographic score of capillary density and dermal temperaturein the thigh muscles were greater in groups 4-，6-，and 8- day than in groups 2 and 3 day. Conclusion Within 2 and 3 days，the replanted limbs of SD rats will necrose because of vein-occlusion; and 4 days later the replanted limbs can survive depending on the reflux-vein of new collateral veinlet.
